Stapler



June 5, 1951 H. G. SACHLEBEN 2,556,002

INVENTOR June 5 1951 H. G. sAcHLEBl-:N 2,556,002

sTAPLER Filed Sept. 29, 1947 1 4 Sheets-Sheet 2 INVENTOR June 5, 1951 Filed Sept. 29, 1947 H. G. SACHLEBEN STAPLER 4 Sheets-Sheet 5 1 M .f ATTORNEY June 5, 1951 H. G. sAcHLx-:BEN 2,556,002

STAPLER Filed sept. 29, 1947 4 sheets-sheet 4 INVENTOR ATTO RNEY5 Patented June 5, 1951 unirse sini-srs Partnr orelcli:

STAPLER Harold G. Sachleben, Bellmawr, N. J., assigner to Acme Staple (llompany, Camden, N. J., a corporationof New Jersey Application September 29, 1947, Serial No. 776,699

5 Glailrs- My invention relates` to Staplers of the char.- acter which will cut off a staple from a strip and apply the staple to the work, preferably clinching the staple in the work.

A purpose of my invention isA to facilitate the application of double staples particularly by preventing misalignment of the staples during appucsuon.

further purpose is to support the staple, preferably of double character, during. the shearinglby holding the staple against the forward end of, the shear-plunger during the shearing operation.

A further purpose is to hold the` bar of the staple against the forward end of the plunger l during the advance of the staple down the guideway toward the work.

A further purpose isV to hold the bar. of the staple. against the front ofthe plunger by mechunsm mounted. on the` plunger so that. staple will return up, the guideway with the plunger Ain case. the forward stroke is4 not completed.

A' further purpose is to4 support the staple between its1 legs from the plunger during` the initial insertion ot the4 staple into the work te prevent premature closing. ofl the staple. during the be ginning of. theA operation of driving` the staple and to withdraw the` support prior to clinching the. staple.

A further. purpose is` to mount a finger on the plunger of a stapler and to grip the staple preferably. at the bar and in advance of the staple and pressit against the plunger.

A further purpose is to pivot the linger on the. plunger.

vA further purpose is to prov-ide lost motion between the iinger and the plunger near the endet the stroke of thev plunger, preferably by pivoting the linger on the wall of a longitudinal slut at one side of the plunger suitably op- Y,pnsite to the sideY from which the staple feeds.

A furtherk purpose is to'swi-ng the grip eXtension of4 the nger out of the path ot the plunger before the staple is fully driven.

A further purpose is to cam the iinger out of the way` of the plunger, suitably by a cam surface on the linger engaging an abutment.

A further purpose is to 'provide a cam enlargement on the guideway` to receive the finger as it moves out oi the plunger and to assist in moving the finger back into position on the forward face of the plunger.

Further purposes appear in the specification and in the claims.

In the drawings I have chosen to illustrate a 2 few only of the numerous embodiments in which my invention may appear, choosing the forms shown from the standpoints of convcnielfle in illustration, satisfactory operation and clear demonstration of. the principles involved.

Figure 1 is a fragmentary side elevation, partly in central vertical section, of my improved stapler.

Figure 1a is a fragmentary perspective showing` the engagement o1" lug 46 on follower liliA with stopt! on theside of housing 55.

Figure 2 is an enlarged top plan View ofthe .Staple guideway shown in Figure 1.

Figure 3 is an exploded` perspective view of the main operating elements, showing a guideway in central vertical section corresponding to that of Figure 1, and showing a shear blade. broken away at the support.

Figure 3a isa perspective showing a modication of the staple of Figure 3.

Figure 4 is a fragmentary rear elevation of the shear-plunger.

Figure 5 is a fragmentary side elevation of the shear-plunger.

Figure 6 is a fragmentary enlargement of Figure 1, showing the beginning of the operation.

Figure '7 is a fragmentary front elevation of the plunger and nger gripping the stapler. in the position of Figure 6.

Figures 8, 9 and l0` are views corresponding to Figure 6 and showing the progressive advance in the operation of Figure 6, Figure 8 showing the staple` after shearing, Figure 9 showing the staple entering the work and Figure l0 illustrating the clinching.

In the drawings, like numbers refer to like parts throughout.

Describing in illustration, but not in limitatin, and referring to the drawings:

In the prior art diiliculty and malfunctioning has been encountered in Staplers, due to the wide4 variation oi the operating conditions, particularly when the devices are manually operated. shearing is sometimes accomplished with such force that the staple is either twisted angularly with respect to the guideway by the shearing ac-ition itself or given such impetus down the guide# way that it proceeds ahead of the plunger and is likely to be deflected and jammed in the guideway. These difculties are particularly prevalent with multiple-legged staples (that is, staples hav ing at least two legs on each side, or normally four legs), since such staples are` wider in the bar and more likely to be subjected to torque in the shearing operation.

In accordance with the present invention the type havingrat least two legs at each side.

Will be evident, however, that the invention may the length ofthe legs of the staple.

bar of the staple, preferably a Vmultiple staple but permissibly a single staple, is gripped against the forward edge of the plunger during the shearing from the strip of staples, and also during the motion through the guideway, during the return motion in case the staple is not inserted and during the final phase of the entry of the staple into the work.

The gripping against the front of the plunger is accomplished by a nger Vor the like mounted on the plunger and preferably pivoted with respect to the plunger and having lost motion in relation to the plunger during the end of the forward stroke. The finger is suitably pivoted about a wall of a slot in a side of the plunger, preferably opposite from the side from which the staple enters the guideway. The swinging of the finger is preferably accomplished by a cam projection on the linger which engages an abutment, and the guideway is suitably widened to receive the swinging finger and to provide cam surfaces to'aid in returning the cam finger to its aligned Aposition on the retraction of the plunger.

The drawings show a stapler 26 intended to represent one of the prior art types, which einploys a strip of staples 2| of channel shape having forwardly 'directed legs 22 on either side of the staple and a bar 23 joining the legs. The legs are preferably pointed, as well known, and in thepreferred embodiment will be of multiple It mit raising of the stapler off the work or lowering to the operating vposition shown.

Mounted on the arm 26, at a suitable position behind the' front of the stapler, is a pivot 21 for Van actuating arm 28, which is pvotally connected The rod 3c may 'be'depressed in any suitable manner as by a pedal to pull down on the actuating arm 28.

at 29 to a connecting rod 30.

The actuating arm 28 is retracted by a spring 3l engaging'the under portion of the actuating arm at 32; at one end, and at the other end 'engaging theabutment 33 on the arm 26.

At theV forward end of the actuating arm 28,

' pivotal connection is made at 34 with a plunger head 35, which moves up and down Vin guides 36 and suitably connects at 31 with ashear-plunger 33,y capable of vertical motion in a guideway 39. The shear-plunger 38 suitably carries at its rearward edge a tool steel shear 4l conveniently fabricated as an insert to the plunger, and cooperating with a shear blade 42 having its shearing edgein line with the rearward edge of the plunger, and located between the legs of the staplesin the strip. The shear blade 42 is'pref- .erably supported on the end of a channel ele- "ment 43 of width less than'that of the bar of the staple being' used, and of height greater than The staple strip 2l is conveniently progressed along the rib 43 toward the front of the stapler with the legs of the'staples straddling the rib, as shown, and the;bar of the staples resting on the top of the rib for support.' A feed passage 44 above and on each side of the rib guides the staple strip.

the staple strip and having a side lug 45 extending upwardly and engaged by spring abutment 4l, which connects to tension spring 48, attached at the other end to spring abutment 49. The follower 45 is limited in forward travel by a stop 5i engaging the follower side lug 4G.

In clinching the staples, the stapler employs an anvil 52 at the bottom of the staple guideway which suitably has a tool steel insert 53 to engage the ends of the legs of the staple.

The guideway through which the forwardmost staple 54 is progressed after shearing, is suitably contained in a guideway housing 55 which, as best seen in Figures 2 and 3, includes staple guiding parallel Walls 56 for engaging the legs of the Vstaple and the ends of the bar of the staple, staple guiding walls 51 taking the form of shoulders to engage the front side of the bar of the forwardmost staple and staple guiding w-alls 58 for engaging the back side of the bar of such staple. Between and beyond the shoulders 51 are provided parallel walls 59 Vfor engag- -ing the ends of a staple gripping finger to be described, and walls Si which extend transversely of walls 59 for engaging outside of such finger. liorwardly beyond the guideway for the finger is a cam extension receiving slot B2 located between transverseV walls 6 I The side of the shear plunger 38, opposite from the shearing and opposite from the direction from which the feed passage comes, is slotted -at 63 back of the forward end to provide pivotal action and lost motion to be described for the gripping finger. The slot 63- preferably extends in from the front end of the plunger and for a substantial distance along the Vlength of the plunger, as shown. Y

A finger 64 is mounted on the forward face of the plunger or the opposite face from that toward the strip of staples. The nger consists of a body7 65 which normally lies against the side of the plunger, a laterally extending gripping extension 66 across the forward end of the plunger from the side opposite from that from which the ,staples are fed, a pair of rearpivot ends 61 which engage and pivot on a forward surface 68 of the slot 63, and an oppositely directed-cam projection t9 which engages in the cam receiving slot 62. The pivot ends El are preferably Yon either side of the inger and the cam projection 69 isrin the center as seen in Figure 7. Near the lower end of the cani receiving slot 62 a cam abutment 1I is provided and below the abutment the'shoulders 6l, which engage the outside of the finger,

are diverged from the path of the plunger to provide cam surfaces 12.

The operation will be best understood Vby reference to Figures 6 to 10 inclusive, which illustrate successive operative steps.

In Figure 6 the device is shown in its inactive position at the beginning of a cycle. The finger body is'in'line with the side of the shear plunger opposite from the shear and opposite from the direction from which the staple strip feeds. The ends 61 of the finger engage the Abottom wall 68 of the slot in the side of the plungerwhile the extension 66 across the forward edges of the plunger 38 continues, from the side op-posite to that from which the staple strip feeds, between the opposite legs of the forwardmost staple, to a `position approximately below the line of shearing 13 (Figure 6), where the line of the shear 4I and the shear blade 42 passes through the staple strip.

. When the arm 20 is forced clown against the action ofv the spring 3i! by: the connecting rod 301 the shear-plunger travels downwardly. froml the position of Figure 6. to-the positionof Figure 8. It will be noted in the position of Figure 8 thatthe linger mounted on the shear plunger maintainsapositicn in whichits body lies against the side'- of the shear plunger. and is so held by the guideway surfaces or shouldersvl.. Thebar 23 of the staple has been sheared 01T from the strip by the cooperating action of.v the shea-r 4l andfshear blad'es42. The extension on thefinger passes vbetween the opposite legs of. the forwardmoststaple and grips the bar of the staple against the forward edge of the plunger, preventing. the possibility of. angular displacement or cantingof the forwardmost staple as it moves down the guideway. It will be evident alsothat during the shearing action, if the finger werenot employed, the shearing would exert a torque or twisting tendency on the bar of. the forwardmost staple. Itwill be evident from. Figures 6, '7 and 8, however, that theextension on the finger gripping the`bar of the staple between the legs of the staple prevents twisting under the shearing action. This is particularly important because in a double staplethe bar is comparatively wide and the lever arno on which torque can be appliedis,V

therefore, much increased. This featureis, therefore, especially important in multiple legged staples such as double legged staples.

.Normally the operation will continue by pressing th'plunger further along theI guideway, but if the pressure should be released from the plunger in aposition such as that shown in Figur-ef 8, due for example to the fact that the operator has changed his mind and reconsidered the action of stapling, the present invention will act to prevent stoppage by holding the bar of the staple against the forward face of the plunger inthe position of Figure 8 as the plunger moves up again to the` position of Figure 6 under the action yof the retraction spring 3|. When the plunger returns to the position of Figure 6, the feeding mechanism including the feed-i spring and follower will' be prevented from advancing another staple due to the fact that the forwardmost staple is still gripped by the linger and the insertion of' another staple under the finger extension in the position of Figure 7 is not possible until the previous staple has been driven.

If now the stapling takes its normal course, the next position reached will be that of Figure 9. In'this position the forwardmost staple has advanced to engage the work 1141. There is sometimes a tendency at this point for the legs,v of

the staple to close before the points thereofl have fully encountered the, anvil. lIfhis may cause the staple to close or partially close before it has gone through all of the plies or all of the thickness of the work. SuchV action is highly undesirable, as it may prevent the staple from gripping or `may cause the staple to tear the work. It will be noted in Figure 9 the extension 66 on the finger is still in position between the opposite legs of the staple to prevent premature closing at this point.

During the movement of the plunger through the positions of Figures 6 and 1, the cam 69 travels down the cam slot 62 without encountering any cooperating surface or performing any cam function. In the position of Figure 9, however, the cam engages the abutment 1I and at the same time the body of the finger reaches the position opposite the cam enlargement 12. The effect of further downward movement of the plunger toward the position ofr Figure L0` :is now to` pivot the finger about the cam 69 and pro,.- vide lost motion of' thepivot ends 61 inthe slot 63. This..` lost motion. is clearly shown in- Figure 16.

The `body ofthe Iinger'swings .over and engages the surfaces 12 and this withdraws the forward extension 66 from-in front of. the plunger. Byv the time the withdrawal has become effective the staple has been driven. far enough so that the ends of the legs are ready to engage the anvil. Accordingly the staple is. clinched by the anvil in the position. of Figure 10.

Onthe retractionstroke the reverse action will take place, except that no staple will bepresent if. the staple hasbeen` driven as above described. During retraction between the position of Figure 10 andthe position of Figure 9 the lost motionin the slot63 will be made up, the nger will swing` into thevertical. positionaided by the upwardA force on end 61., the pivotalV action. of cam a9. against abutment 1|, andto some extent by. a-

face cam. action by surface 12. As soon :as the ringer. attains the position of Figure 9, the remainder of the retraction will simply consist of upward movement of the-plunger and finger together to the initial position at which the. next staple will` feed.

It will thus be evident that the lingerY of the present inventionsupports and positions thesta.-

ple during shearing and progress through. theguideway, prevents premature` clinching and returns the staple without causing a stoppage in case the plunger is given a false start.

It will be evident that the staple slot is formed by surfaces 56, 51 and 58` in the plunger guideway housing. The finger slot opening 59` connects at one side with thestaple slot, and the ,cam slot 62 connects at the other side with the finger slot. The finger slot is enlarged for cam` abutment 12. The feed passage is provided at 44. The plunger has. a slot 63 on its side.

In view of my invention and disclosure variations and modiiications to meet individual whim or particular need will doubtless become evident to others skilled in the art, to obtain all or part of the beneiits of my invention without copying the process and structur-e shown, and I, therefore, claim all such insofar as they fall within the reasonable spirit and scope of my claims.

Having thus described my invention what I claim as new and desire to secure by Lette-rs Patent is:

l. In a stapler, walls forming a staple driving guideway, walls forming a transverse staple feed passage for channelshaped staples in a continuous strip, a shear blade adjacent the junction between the guideway and the feed passage, andfa shear plunger in the guideway cooperating with the shear blade, in combination with walls forming an elongated slot in the side of the plunger opposite from the feed passage, a finger having a pivot portion engaging in the slot when in shearing position and having lost motion movement along the plunger rearwardly of the slot near the end of the driving stroke, having a body extending along the side of the plunger opposite from the feed passage and forward of the slot and having an extension across the forward end of the plunger forward of and engaging the staple and into the space between the sides of the forwardmost staple, and cam means for swinging the iinger extension out of the path of the plunger before the staple is fully driven.

2. In a stapler, walls forming a staple driving guideway, walls forming a transverse staple feed Y passage for channel shaped staples in a continuextending along the side of the plunger opposite Vfrom-the feed passage and forward of the slot,

having'a cam projection opposite from the pivot portion at the pivot end and having an extension acrofss the forward end of the plunger forward of and engaging the staple and into the space between ;the sides of the forwardmost staple, an abutment along the guideway in position to engage the cam projection before the staple is fully drveniand cam walls on the guideway against which the finger swings from in front of the plunger at the end of the forwardstroke and which swings the finger back-against the-plunger on the retraction stroke. l

3. Ina stapler, walls forming a staple driving guideway, walls forming a transverse staple feed passagel for channel shaped staples in a 'continuous-strip, a shear blade adjacent the junction between the guideway and the feed passage, and a shear plunger in the guideway cooperating with the shear blade, in combination with walls forming an elongated slot in the side of the plunger opposite'from the feed'passage, a finger having a pivot portion engaging in the slot when in shearing-position and having lost motion movement along the plunger rearwardly of the slot near the endof the driving stroke, having a body extendingalong the side of the plunger opposite from the lfeed passage and forward of the slot, having a cam projection opposite from the pivot por-V tion'atV-the pivot end and having an extension across `the forward end of the plunger' forward of and engaging the staple and into the space between the sides of the forwardmost staple, an abutment along the guideway in position to engageV the cam projection after the staple has entered the work and before the staple is fully driven and cam walls on the guideway against which'the finger swings from in front of the plunger :at the end of the forward strokerand which swings the finger back against the plunger on 'the retraction stroke.

` 4.' .In`a stapler, a plunger guideway housing .having three slots extending therethrough, the

Y, enlarged4 at one end away from the staple slot,

and the third of. which 'is a cam slot extending parallel with the finger slot, narrower than the finger slot, and laterally communicating with the finger slot on its 'side remote from the stapleslot, a plunger moving longitudinally in the staple slot toward the enlargement in the finger slot and having a forward face, a finger pivotally mounted on the plunger on the side toward the linger slot, moving longitudinally in the finger slot, having an extension across the forward facerof the plunger from the side toward the finger slot and having a cam extension moving in the cam slot and acam abutment in the cam slot for engaging the'cam Vnear the end of the travel of the plunger, the enlargement of the finger slot permitting swinging of the nger away from the plunger upon engagement of the cam with the cam abutment.

5. In a stapler, a plunger guideway housing having three slots extending therethrough, the first of which is a staple slot, the second of which is a finger slot extending parallel to the 'staple slot, narrower than the staple slot, laterally communicating at one side with the staple slot and enlarged at one'end away from the staple slot, and the third of which is a cam slot extending parallel with the finger slot, narrower than the finger slot, and laterally communicating with the linger slot on its side remote from the staple slot, a cam abutmentin the cam slot adjoining the enlargement, walls forming a feed passage for channel shaped staples transverse to the staple slot and extending into the staple slot Yfrom the side remote from the finger slot, a shear blade in line with the point of joining of the feed passage andthe staple slot on the side remote from the finger slot, a plunger moving longitudinally in the staple slot toward the enlargement in the -nger slot and having a forward face, a shear on the plunger cooperating with the shear blade, walls forming an elongated pivot slot-on the side of the plunger adjoiningy the finger slot and behind the forward face on the plunger, and a n-V ger having a body in the finger slot, having pivot ends normally adapted to engage and pivot on a wall of the pivot slot in the plunger, having a cam extending intoA the cam slot and in forward position engaging the cam abutment to displace Y the finger into the enlargement, andhaving-an extension across the forward face of the plunger from the nger slotvtoward the opposite wall of the Staple slot forward of the staple.

' HAROLD G. SACHLEBEN.

REFERENCES CITED The following references are Vof record in the file of this patent: Y r

UNITED STATES PATENTS Number Name Date` I 662,495 McKay Nov. 27, 1900 2,140,588 Krantz r Dec. 20, 1938 

